Advanced Semiconductor Engineering Issues Open Letter to Siliconware Precision Industries Shareholders

To the Honorable Shareholders of Siliconware Precision Industries Co., Ltd.: We would like to report the successful results of our tender offer (the "Tender Offer") for the common shares (the "Common Shares") and the American depositary shares (the "ADSs") of Siliconware Precision Industries Co., Ltd. ("SPIL"). Our Tender Offer was well oversubscribed, and we express our sincere gratitude for the support we received from those of you who supported our Tender Offer. The number of Common Shares (including those represented by ADSs) validly tendered and not withdrawn in our Tender Offer was 1,147,898,165 (representing 36.83% of the issued and outstanding share capital of SPIL), a number which significantly exceeded the offer cap of 779,000,000 Common Shares (representing approximately 24.99% of the issued and outstanding share capital of SPIL). The results of our Tender Offer provide a market view affirming that our price of NT$45.00 per Common Share was a fair one, and it also affirms our strong belief that the market sees the compelling rationale for our investment and the future collaboration between SPIL and ASE, in a manner consistent with all applicable laws and taking into account the rights and interests of